The invention relates to the new use of antiestrogens for the production of a pharmaceutical agent for treating a relative androgen deficiency in men.
In men, increasing age leads to a reduction of testicular androgen production and androgen concentration in the organism. In contrast to the situation in women, in whom estrogen production drops to castration values within a comparatively short period, this takes decades in men and involves a gradual drop. The total concentration of testosterone in the serum in the older age group is significantly reduced compared to the values in young men. Because of the increase in steroid hormone-binding globulin (SHBG) that coincides with the aging process, moreover, the proportion of free, unbound, and thus biologically active testosterone drops. In addition, the serum levels of estrogens, although they are produced from androgens by direct conversion, do not drop in the same way as a function of age. As a result, the hormonal environment is significantly altered.
In men, the hormonal environment of the sexual steroids is characterized by a significant preponderance of androgens over estrogens. While the circulating main component of androgens, testosterone, is detected in the serum in units in the range of nmol/l, the estrogen antagonist, estradiol, can be measured only in the range of pmol/l. This considerable preponderance of androgen can be detected basically in the entire late puberty period of life, but there is a clearly different intensity of this androgen dominance as a function of age. With increasing age and particularly so in those over the age of 60, there is a less pronounced emphasis of the androgen preponderance.
In older men there are relative decreases in the preponderance of testosterone by 30-50% compared to the previous values found in young men.
The relative testosterone deficiency per se can be regarded as responsible for a number of age-related disorders. Reduction of muscle mass accompanied by limitation of body performance capacity, reduction of bone density and in individual cases even osteoporosis, an increase in prostate size referred to as benign prostatic hyperplasia, reduction of libido and potency, and psycho-vegetative disorders such as depression, which are disorders that are often generically referred to as Male Menopause and are caused by relative androgen deficiency in men. Libido is the desire to obtain an erection, while potency is the ability to have that erection.
It is known that in younger men, testosterone values are also effectively increased by daily treatment with antiestrogens to treat male infertility. Treatment of Male Infertility, Springer-Verlag Berlin, Heidelberg, New York 1982; Fuse, H. et al., Archives of Andrology 31 (1993) 139-145); Nonsurgical Treatment of Male Infertility, Jarow, J., Infertility in the Male, pp. 410-422. However, it has been thought that antiestrogens do not seem well suited for treatment of a relative androgen deficiency in men. Thus, for example, U.S. Pat. No. 5,861,389 proposes the use of at least one aromatase inhibitor for the production of a pharmaceutical agent for treating a relative androgen deficiency in men.